The tendency of hard-core Republicans to believe that all of the economic developments under the Obama presidency were detrimental to the nation illustrates the

A) confirmation bias.
B) framing effect.
C) overconfidence effect.
D) availability heuristic.

Confirmation bias is the tendency to search for, interpret, favor, and recall information in a way that confirms one's preexisting beliefs or hypotheses, while giving disproportionately less consideration to alternative possibilities. In this case, hard-core Republicans believing that all economic developments under Obama were detrimental illustrates this bias, as they are likely to focus on information that supports their negative view and ignore information that might present a more balanced or positive perspective.